Manhole construction



@m 141, um. l www? W. C. MGGAFFIC MANHOLE' CONSTRUCTION Filed Dec. l. 1923 A 7 To 14 tiffateniited @et ld, i945.'

WALTER CLINE MCGAFFIC, 0F YOUNGSTOWN, OHIO, ASSIGNOR T0 THE YOUNGSTOWN BOILER & TANK COMPANY, OF YOUNGSTOWN, OHIO, A CORPORATION 0F OHIO.

MANHOLE CONSTRUCTION.

Application filed December 1, 1923. Serial No. 678,073.

T 0 all whom t may concern.'

Be it known that I, WALTER CLINE Mo- GAFFIC, a citizen of the United States, and resident of Youngstown, in the county of Mahoning and State of Ohio, have invented certain new and useful improvements in Manhole Constructions, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to manhole constructions and has for its principal object the provision of a manhole construction of increased strength and of greater economy in production and installation.

Other objects of the invention will appear from the following detailed description thereof.

In the drawings :m

Figure 1 is a perspective of a manhole constructed in accordance with this invention;

Figure 2 is a perspective of the frame which forms a part of my improved manhole;

Figure 3 is a diametric section of a manhole constructed in accordance with this in vention.

The numeral l indicates the frame for my new manhole construction. Said frame is of unitary solid plate construction, and is flanged inwardly as shown at Q. in Figure 2.. The frame l is provided with bolt holes 3 in the flange in any suitable number, arranged to receive bolts 4, the heads 5 of which are preferably welded to the under side of the flange, the bolts thus being permanently affixed to the frame. Adapted to fit upon the frame l is a cover 6, the same being preferably of concave-convex shape. The flange 7 of the cover is provided with bolt holes to receive the bolts 5, and the cover is secured to the frame by means of the usual nuts 8, the convex surface of the cover being to the outside as shown.

When a tank or pressure vessel is provided with a manhole construction in accordance with this invention, it will be noted that the hole and cover are close to the tank or vessel. By reason of the solid frame construction as above described, in connection with the cover featuresias set forth, my new l manhole is particularly adapted to eect an absolutely tight closure, and is furthermore peculiarly adapted to resist high pressures. When used on pressure tanks the construction herein set forth is particularly convenient for the reason that the cover is on the outside of the manhole, whereas in the constructions heretofore in use, it has been found necessary to install the cover on the inside.

As a further feature, it will be noted that the manhole frame l can be conveniently pressed into the shell of the vessel or head at the time the same is constructed, thus eliminating a large amount of labor required for the installation of a separate manhole on the tank or vessel.

Having thus fully described my invention, what I claim as new, and desire to secure by Letters Patent, is

l. A manhole construction comprising a unitary frame, said frame being substantiallv Z-shape in cross-section and the upper flange thereof being inturned when the frame is in position, a cover adapted to t upon said inturned flange, and means for securing said cover thereto.

2. A manhole construction comprising a unitary frame, said frame being substantially Z-shape in cross-section and the upper flange thereof being inturned when the frame is in position, a cover adapted to fit upon said inturned flange, said cover being of concave-convex construction, and means for securing said cover thereto.

3. A manhole construction comprising a unitary frame, said frame having an inn wardly turned flange, bolts permanently secured in said flange, a cover adapted to fit upon said flange, said cover being provided with perforations for said bolts whereby the cover may be secured to said flange.

a. A manhole construction comprising a unitary frame, said frame having an inwardly turned flange, bolts permanently secured in said flange, a cover adapted to fit upon said flange, said cover, being of concavo-convex construction, and being provided with perforations for said bolts whereby the cover may be secured to said flange.

l/VALTER CLINE MCGAFFIC. 

